Adjustable overload spring device



Nov. 10, 1953 J, ALLETTO 2,558,749

ADJUSTABLE OVERLOAD SPRING DEVICE Filed May 11, 1951 2 Sheets-Sheet 1 Nov. 10, 1953 A. J. ALLETTO ADJUSTABLE OVERLOAD SPRING DEVICE 2 Sheets-Sheet 2 Filed May 11, 1951 IIII'I/I/I/I/III Patented Nov. 10, 1953 omen STATES PATENT OFFlCli a 2,658,745 ADJUSTABLE OVERLOAD sntntu DEVIGE Alexander J. All etto Chicago, Ill Appfieatioa Ma-y ii, 1951; Serial fie; fist-7t? 6 Claims. (on 267-255) a 1 'mie'invefition relates to an adjustable overload spring device ada ted ie'r use between two spring separated support members and capable of adjustment sun as to prevent too great a variatwn in the eistanee thre'between under 5 varynig leadsi While not limited thereto, it is especially adapted for use in automotive v'eliiizls in adjusting 61 the amount (if deflection or eompression in me main load carrying: springs; so as to be able to bring them back to an apio'foxim ately normal level fegatdiees of the amount of the load, ate in trucks ueea tor carrying neavy loads, aute mobiles needfor rial-ling trailers, 'aLnl other instances whefesueneompensiation inlevel is desired. The use of the device in connection with tiieieatspringe of automobne need for dra ing' a tfatilei has been shown 01 illii'strative pufiies'es only; in the di iwifig-S. v Ae is; well known the amour-it of load onthe rear sfifmgset an automobile varies considerably at aifieient tifi'i'is when handling a traner tnefenenma, Fer efia-fr'l fil a Shift of t" load in the tftilei from rear touro'r'e or t me verse; 01'? the placing 6? heavy bjts 110 I as f-iifliitiife, re;- frigerators, aizid t-H' lili tore of aft, 61' the; presenee of severai passefigere one eilldfiif the dune? Withoiit proper dietfibii'tion; win eaase itl'i'er toe muenload on th' re-at sinfizig of the eel?" d bring the name of the against the axlehoixeing, or win cause a tenae'nea t6 lift the rear em of the ear too high;- lfi additifi'ii ti) being ifijurione to the car sittings, r iitlif the car 1102* the trailer' will tide as it she also when th ear strings have een eente tenant activated to permit a considerable read the front of the trailer with ons'id'fiabl 'we"ht on the fear springsof the can ne aiseom ietmg or the trailer from the ear for a ti-it' to town the car alon will eaiiee embarrassment t3? spring detio; to pi'dvi-de a device of the type referred to in which easy and quick adjustment may be made when desired to adjust the distance between two spring sepaiate'd load bearing supports, in order to compensate fo'i' different amounts" of lead thereon; to provide anadjustable overload spring device for the load bearing springs of an automotive vehicle for returning the frame of the vehicle to an approximate normal height under different loads applied thereto; to provide an aajtis'ttble overload p rif1g device fof the rear ma sittings of an automobile used for drawing a trailer, siich thatby easy adjutment said body springs may be brought back to approxiinatly ndfmajl height under different loadings in the trailer as well as when the tiaile'r is reinovd from the automobile; to irro'tide a device of the type referreet to which. will by east adjustment be of great assistance in detaching a trailer from a car, in changing a tire, in using the cahalone after the ti'ailer is detached there'iiom, in equalizing a weak spring, and for compen' setting Grown?- 6f road of laterally inclined roadej and even further objects, advantages, and capabilities inherently possessed by my device, as will later" more riilly appear.

My invention further resides in the fiox'nbiilat tion, construction; and arrangement of parts iliustratedthe aeeompanying drawings, and while I have shown tner'ein' a referred mbhdi' rnent, I wish it mder stood that the same is suseptibl' 6i modifiaition and change without dfififitin'g fIGfi l the s'pifit 61 my invention.

in the drawings: V

Fig. I is ajr agtnentaty side elevation of the rear pertiom at an a teinebne and; the front per tion 61 a traiierg and showing in dotted lines we e eet orheavy eaasin the ffbnt Of the tfail'r'; fid- Sfilid lirf the normal po sitidri (if tlie's'' pairt after etdiiis'tffl'fit 6f Iiiy pr'S'ent in= ventidn;

Fig. is; a fragmentary p'i sp'tiv view f the rear end of an automobile" Showing the l'ifiid'i end the adtnsting' rod: or post aocessible for operation the magage compartment;

Fig} 3' is an enlarged, fr'agmentaty, longitudinal: Vitiil? seetion (ii the aidjntttbl' overload siJi-i'r-ig device; on lifie we of Fig. 4.

me, 4 is a fragmentary; transvefse, vertic'ai setiefi on the 4:4 of- Fig. 3;

Fig. 5 is; en-Iargeu: fragmentary, transverse; Vft' 'jl sectitii-i en line 5'5 of 3; and enowiag the aajuetf bie fi'iirloaki spring device normal no ltd position;

be used in many other instances where it is desired to adjust spring separated load bearing parts to a normal level or separated position regardless of the amount of load applied thereto. In the form shown in the drawings the automobile I is provided with the usual rear axle housing 2, a frame or chassis 3, and springs 4 of any suitable type for resiliently and yieldably mounting the car frame on the axle housing to permit the frame and axle housing to have movement toward and away from each other depending upon the load and road conditions.

Fixed within the channel of the frame 3 is a suitable length of steel channel bar 5 having its flanges welded, or otherwise secured as desired, to the inner faces of the flanges of the frame, and having its web approximately flush with the inner edge of the flanges of the frame, as seen in Figs. 4 and 8. Said Web of channel bar 5 is formed with a central hole 6 within which is .mounted the neck of a collar 1 formed with an annular flange to bear against the inner face of the web of the channel bar 5, as shown in Fig. 8. Positioned inside of the car frame and slightly spaced from the web of channel bar 5 is a bracket member 8 of channel shape in cross section and extended downwardly at its inner end (see Figs. 4 and 8) Welded, or otherwise rigidly secured, to the inner edge portions of the'flanges of bracket 8 is a spring carrier or housing 9, which in the form illustrated is a cylinder, although it may assume other forms if desired, Positioned between the cylinder 9 and the web of the channel shaped bracket 9, prior to securing these two parts together, is a head It of ashort shaft II which passes through a hole in the web of the bracket and through hole 6 into the space I within channel bar 5 where its diameter is reduced to provide a shoulder I2 against which is seated a conical member I3 having a central opening positioned over the reduced diameter of shaft H and fixed thereon by nut I I threaded onto threads on the shaft II. The opening in collar I directly opposite the conical portion of conical member i3 is formed with a complemental conical surface against which conical member I 3 seats with sufficient firmness to prevent looseness but yet permit a slight amount of rotation of shaft II with relation to the frame, as well as a slight amount of rocking.

Surrounding shaft I I and gripped between the adjacent faces of bracket 8 and the web of channel bar 5 is 'a fiber washer I5, which under substantial force will yield to permit some distortion of the mounting of cylinder 9 when the car springs and their mountings, and the axle housing, are unduly distorted or moved with relation to the frame in other than the normal up and down movement of the car springs. Also the short shaft II and conical member I3 of the mounting of the bracket on theframe, will permit whatever swinging of the cylinder 9 and 4 bracket 8 may be necessary by forward or rearward movement of the axle housing with relation to the frame, under stress of road conditions. The conical member I3 and shaft II will be of any suitable metal, while collar I may be of either metal or suitable composition material as desired.

As seen in Figs. 3 and 4, the usual clamping plate under the bottom of the middle of the spring 5, for clamping the spring to the axle housing, is replaced by a strong steel plate I6 which extends rearwardly and laterally inwardly and which is formed with a hole in alinement with the vertical center axis of the cylinder 9.

on post-part I9.

As will be understood in Figs. 5-7, cylinder 9 is closed at its top by a head I! fixed thereto, and is closed at its bottom by a head I8 fixed thereto. Each of top cylinder head I1 and bottom cylinder head I8 is formed with a central opening in axial alinement with each other for a purpose about to be described. Extending vertically through the center of cylinder 9 is a two-part post, rod, or shaft comprising a, bottom stationary part I9 and an upper rotatable part 20, which parts respectively pass through the central opening in the bottom cylinder head I8 and the central opening in the top cylinder head I'I.

The bottom end portion of the lower stationary post-part I9 is passed through the hole in the plate I9 and fixed to this plate in a manner to prevent axial movement of the post or rod with relation to the plate, but permit some lateral rocking relative thereto. This connection is effected in the manner shown in Figs. 3 and 4, by threading the lower end of post part I9, and placing a nut 2I above and a nut 22 below plate I6, each of these nuts being tightened against a conical rubber block 23 and 24, respectively, fitted into conical seats formed in plate I6 at opposite ends of the hole through which the post part I9 passes. The conical rubber blocks 23 and 24 are semi-rigid sufficient to hold the post .or rod against axial movement, but permit some rocking movement thereof to compensate for various road conditions encountered.

Referring to Figs. 5-7, the bottom cylinder head I8 is formed with a downwardly extendin neck 25 through which the hole in this head passes to permit the cylinder 9 to slide axially The upper post-part 29 is formed at its top with a square or other non- .circular end 26 to receive a wrench preferably of the ratchet type, to permit quick and easy rotation of the upper part of the post with relation to the lower part thereof. It is also to be noted that the upper post-part 20 passes upwardly through an opening 2! in the floor of the luggage compartment of the car so as to be readily accessible for application of a ratchet wrench thereto from within the luggage compartment. The upper end of the cylinder 9 is directly un derneath the luggage compartment floor.

As will be understood there is one of these adjustable overload spring devices on each side of the rear of the car, but as they are both alikeonly one of them is being described in detail. There is one for each rear spring unit, but they may be applied to any spring unit desired regardless of location.

The rotatable top post-part 20 is formed at its bottom end with a reduced diameter cylindrical extension 28 rotatably seated in a complemental opening 29 in the top of the bottom post-part I9. Extension 28 is formed with a circumferential groove 39 in which is seated the end of a pin 3| ascents fastened in the adjacentwall 'ofpost-part 'l9, .so' as to enable the top post-part 29 to be retaf'ted on "the'bottom post-part t3 but be prevented from "longitudinal movement with relation thereto. Formed in one side "of top post-part -29, and extending iongitudinally therea'long from its bot- 'tom to near its top square headis a groove or keyway 32 to :slidab-ly receive a proiection 33 formed in a pressure plate 34 having a central .hole 35 slightly larger "than postpart 29 to enable pressure plate 34 to slide therealong.

"The inner wall "of cylinder 9 is formed, for a substantial portion of its length from the top downwardly, with screw threads 39 within which movably engage complemented th-reaui-s I termed on the marginal edge of pressure plate 34, so that rotation of top post-part -29 will rotatepressure plate 34 with it and move the pressure plate longitudinally of post-part 20 in one direction or the other depending on the direction of rotation.

iBhe upper end portion of lower post-part :119 is slightly reduced diameter to form a shoulder 38 at a level approximately even, or nearly so, with the upper surface of the bottom cylinder head 1% when the car frame stands at normal unloaded height. The outside diameter of .the upper reduced portion of the lower post-part I9 is the same as the outside diameter of the upper post-part 29. Loos ly but firmly resting on shoulder 38 is an abutment plate or disk 39, the outer diameter of which is slightly less than the inner diametereor the cylinder 1:9, and which has {a central hole enough larger than the upper reduced portion of postpart H) to permit some downward movement of post-part l9 therein should the car tire suddenly drop into a depression or cavity in the roadway, but prevent upward movement of the post-part 19 with relation to the abutment plate 39 when the abutment plate is resting on shoulder 38.

Positioned within cylinder 9 between the abutment plate 39 and the pressure plate 34, and surrounding post-parts l9 and 20, are a number of radially spaced compression coil springs, three in the form shown, which are designated 49, 4|, and 42. Spring 40 is stronger than spring 4|, and spring 4! is stronger than spring 42. I wish it understood, however, that one or more of such springs may be used as desired, depending upon the strength of the spring or springs used, and the load or loads to be carried.

The cylinder 9 being fixed to the frame 3 by bracket 8 and shaft or bolt ll, against vertical movement but laterally rockable with relation thereto, will under no load stand in the normal position shown in Fig. 5. With a capacity load on the car, the frame thereof will move downwardly and compress the springs 49-42 to move the parts into the position shown in Fig. 6, which would mean that the car frame would be striking, or nearly striking, the rubber bumper block 43 on the axle housing. This overload would not only put an excess strain on the car springs 4, but would also put the car in an undesirable cramped position. To overcome this, all that is necessary is to apply a ratchet wrench to the square head 26 of the post and rotate the upper post-part in the appropriate direction to move the pressure plate 34 downwardly within the cylinder, which will raise the cylinder and car frame into the position shown in Fig. '7, which will bring the car frame back to its normal level. Also any intermediate adjustment may be made as desired. .As is clear this will remove the excess strain from the car springs and will position the car frame at its normal or any other desired position.

Should the loadon the car rear springs be caused by a trailer 44 shown in Fig. 1, due to an improperly distributed load therein, the overload spring device of the present invention may be easily operated by a ratchet wrench on the square head 26 to rotate the upper post-part 29 in the desired direction to produce the desired level or height of the car, and at the same time provide the proper level for the trailer. Also when disconnecting the trailer draw bar 'rrom'the car, the rear end of the car, instead of riding too "high, can, bymanipi-ilation of the rotatalbly postpart "29 as described above, easily be brought to the desired level for a trip to town or elsewhere without the trailer.

When the cylinder -9 is moved downwardly from the position of Fig. "5 to the position of Fig.6, and when moved upwardly from the position of 6 to the position of Fig. '7, the abutment plate '39 will act in direct as a "loose piston head with relation to the cylinder, and serve as an abutment or support for the bottom ends of the springs 49-42 which are compressed varying amounts between plates 34 and 39. As stated,

this device will be useful in many instances other "overload spring device, I wish it understood that it can also 'be used as the main spring on any or all of the front and rear wheels of an automobile or truck, to 'replacethe present conventional spring or springs which are not adjustable. It is also capable of use in instances other than with automobiles and trucks.

Having described my invention, I claim:

1. An adjustable overload spring device mounted between the axle housing and frame of an automotive vehicle, comprising, a rod fixedly mounted adjacent its bottom end to the axle housing, an abutment plate on said rod and fixed against downward movement thereon, a spring containing cylinder fixed to said frame to move therewith, a pressure disk having threaded engagement with the cylinder for movement up or down therein upon rotation of the disk, and a coil spring compressed between the abutment plate and the pressure disk, whereby upon rotation of the pressure disk the distance between the axle housing and the frame may be varied.

2. A device as claimed in claim 1, including means for selectively rotating said pressure disk in either direction in the cylinder from above the adjacent portion of the frame, whereby the frame may be brought to its normal height with relation to the axle housing regardless of the weight of the load on the vehicle.

3. A device as claimed in claim 2, said means including the rod being formed of two parts held against separation longitudinally but one part rotatable with relation to the other, and the pressure disk being rotatable with the rotatable part of the rod but slidable longitudinally therealong.

4. An adjustable overload spring device for adjusting the height of the frame with relation to the axle housing of an automobile, comprising, a cylinder mounted on said frame for movement therewith, a rod extending through the cylinder and having a non-rotatable part and a rotatable part, the non-rotatable part being secured to said axle housing, an abutment plate slidable in said cylinder and mounted on said non-rotatable part and held against axial movement thereon in one direction but capable of movement in the oppo- 7 site direction thereon, a pressure plate threadably mounted on-the interior of the cylinder for movement therein in an axial direction, said pressure plate being longitudinally slidable on said rotatable part but rotatable therewith, a compression spring between said abutment plate and said, pressure plate, said rotatable part extending" above the cylinder and having a non-circular upper end, whereby a wrench may be applied to said non-circular upper end for rotating said rotatable part of the rod and the pressure plate for adjusting the height of the car frame with relation to the axle housing regardless of the amount of load on the car. 7

5. An adjustable overload spring device, comprising, a two-part rod having a non-rotatable part and a part rotatable on but held against axial movement on said non-rotatable part, a spring abutment member on the non-rotatable part, a pressure plate on the rotatable part, compression springs between said plates, said rotatable part having a non-circular portion adapted to receive a wrench for rotating the same and said pressure plate, a cylinder enclosing said abutment member, pressure plate, springs and a portion of each of the rotatable and nonrotatable parts of the rod, said pressure plate being connected to the cylinder for axial adjustment therein and being connected to the rotatable part of the rod for rotation therewith and axial sliding movement thereon.

6. An adjustable overload spring device, comprising, a spring housing adapted to be secured to a first support member, a rod passing through said spring housing and adapted to be secured at one end to a second support member, an abutment plate in one end portion of the spring housing and slidable with relation thereto, a pressure plate adjustably mounted in the other end portion of said housing, a compression spring between said plates, means for adjusting the position of said housing with relation to said plates and spring, said rod having a non-rotatable part and a rotatable part, the abutment plate being mountedion the non-rotatable part, and the pressure plate being mounted on the rotatable part, the pressure plate having threaded connection with the spring housing, and spline connection with the rotatable part of the rod.

ALEXANDER J. ALLE'I'IO;

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,044,339 Border Nov. 12, 1912 1,078,057 Mitchell Nov. 11, 1913 2,059,434 Broulhiet Nov. 3, 1936 2,563,423 Samothrakis Aug. 7, 1951 FOREIGN PATENTS Number Country Date 5,168 Great Britain 1914 

